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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

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Data Type:	num:perShareItemType
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Period Type:	duration

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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- References

No definition available.

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The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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-Section 25

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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-Section 30

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-Topic 805

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-Section 50

-Paragraph 1

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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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-Publisher FASB

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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Data Type:	xbrli:monetaryItemType
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Amount due from customers or clients for goods or services, including trade receivables, that have been delivered or sold in the normal course of business, and amounts due from others, including related parties expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables, assumed at the acquisition date.

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Amount of deferred tax asset attributable to deductible temporary differences and carryforwards that are expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of deferred tax liability attributable to taxable temporary difference due within one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Period Type:	instant

The amount of inventory recognized as of the acquisition date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

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-Section 55

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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- References

No definition available.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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-Topic 350

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-Section 45

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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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Cash inflow representing an adjustment to the purchase price of a previous acquisition.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Represents the amount of accrued expenses and other liabilities, assumed at the acquisition date.

No definition available.

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Namespace Prefix:	wts_
Data Type:	xbrli:monetaryItemType
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The amount of fixed assets recognized as of the acquisition date.

No definition available.

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Namespace Prefix:	wts_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Represents the information about net income adjusted to exclude net acquisition-related charges and third-party costs.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Represents the information about net income adjusted to include net amortization expense.

No definition available.

Name:	wts_NetAmortizationExpense
Namespace Prefix:	wts_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the information about net income adjusted to include net interest expense related to the financing.

No definition available.

Name:	wts_NetInterestExpenseRelatedToFinancing
Namespace Prefix:	wts_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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Period Type:

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